public IntervalNode(List <Interval <T> > intervals)
{
if (intervals.Count == 0)
{
return;
}
this.Point = this.FindMedianEndpoint(intervals);
this.LeftIntervals = this.GetIntersectingIntervals(intervals).OrderBy(x => x.Min).ToList();
this.RightIntervals = this.GetIntersectingIntervals(intervals).OrderBy(x => x.Max).ToList();
this.MinPoint = this.LeftIntervals.First().Min.Value;
this.MaxPoint = this.RightIntervals.Last().Max.Value;
this.SpanningInterval = new Interval <T>(this.MinPoint, this.MaxPoint);
//if i.min < v_pt then it goes to the left subtree
var leftSegment = this.GetLeftIntervals(intervals);
var rightSegment = this.GetRightIntervals(intervals);
if (leftSegment.Count > 0)
{
this.LeftNode = new IntervalNode <T>(leftSegment);
}
if (rightSegment.Count > 0)
{
this.RightNode = new IntervalNode <T>(rightSegment);
}
}
protected void SearchInternal(IntervalNode <T> node, Interval <T> searchInterval, LinkedList <Interval <T> > retList)
{
if (null == node)
{
return;
}
if (node.SpanningInterval.Overlaps(searchInterval))
{
//if searchInterval.contains(node.v_pt)
//then add every interval contained in this node to the result set then search left and right for further
//overlapping intervals
if (searchInterval.Contains(node.Point))
{
foreach (var interval in node.LeftIntervals)
{
retList.AddLast(interval);
}
this.SearchInternal(node.LeftNode, searchInterval, retList);
this.SearchInternal(node.RightNode, searchInterval, retList);
return;
}
// point < searchInterval.left
if (node.Point.CompareTo(searchInterval.Min.Value) < 0)
{
// TODO: Could probably do a binary search to speed things up.
foreach (var interval in node.RightIntervals)
{
if (interval.Max.CompareTo(searchInterval.Min) >= 0)
{
retList.AddLast(interval);
}
}
return;
}
// point > searchInterval.right
if (node.Point.CompareTo(searchInterval.Max.Value) > 0)
{
foreach (var interval in node.LeftIntervals)
{
if (interval.Min.CompareTo(searchInterval.Max) <= 0)
{
retList.AddLast(interval);
}
}
return;
}
}
//if v.pt < searchInterval.left
//add intervals in v with v[i].right >= searchitnerval.left
//L contains no overlaps
//R May
if (node.Point.CompareTo(searchInterval.Min.Value) < 0)
{
foreach (var interval in node.RightIntervals)
{
if (interval.Max.CompareTo(searchInterval.Min) >= 0)
{
retList.AddLast(interval);
}
else
{
break;
}
}
this.SearchInternal(node.RightNode, searchInterval, retList);
return;
}
//if v.pt > searchInterval.right
//add intervals in v with [i].left <= searchitnerval.right
//R contains no overlaps
//L May
if (node.Point.CompareTo(searchInterval.Max.Value) > 0)
{
foreach (var interval in node.LeftIntervals)
{
if (interval.Min.CompareTo(searchInterval.Max) <= 0)
{
retList.AddLast(interval);
}
else
{
break;
}
}
this.SearchInternal(node.LeftNode, searchInterval, retList);
return;
}
}
public IntervalSkipList(List <Interval <T> > intervals)
{
this._head = new IntervalNode <T>(intervals);
}